JP4772244B2 - Low stress relaxation elastomeric material - Google Patents

Description

表１のエラストマー状組成物の押出単層フィルムの物理的特性を表２に示す。これらの物理的特性は上記の試験方法により測定する。表２に示す物理的特性はすべて等しい坪量のフィルム試料で表してある。表２は、ポリスチレンを低分子量芳香族炭化水素樹脂で置き換えることにより、驚くべきことに、立体的な絡み合った網目構造を構成する組成物の総重量％は減少するが、同等の弾性および応力緩和特性が得られることを示している。
【０１３３】

表３に示す組成物１の物理的特性は、押出単層エラストマー状フィルムとして、共押出した多層フィルムとして、および立体的な真空成形ウェブとして測定する。
【０１３４】
平らな共押出した多層フィルムを製造し、次いで上記の方法により、図９〜１１の顕微鏡写真に示す様なエラストマー状ウェブに成形する。共押出したフィルムは、図４に示す様に３層を含んでなる。中央のエラストマー層は、ポリスチレンおよび鉱油、および所望により芳香族炭化水素樹脂と混合したスチレン系トリブロックを含んでなる。エラストマー層は典型的には厚さが約０．０５２ｍｍ（３．２ミル）である。表皮層はポリオレフィン材料を含んでなり、それぞれ典型的には厚さが約０．００３８ｍｍ（０．１５ミル）である。フィルムの総寸法は約０．０９ｍｍ（３．５ミル）であり、エラストマー層が厚さの約７５〜９０％である。この分野で一般的に公知の方法により、厚さが約０．０７２ｍｍ（２．８ミル）である単層エラストマー状フィルムも製造する。これらのフィルムを上記の試験方法に従って、適当な試料サイズに切断する。
【０１３５】
正確に測定するのは困難であるが、立体的なエラストマー状ウェブの第一表面から第二表面への寸法は、約１０：１の吸引比に対して、１ｍｍのオーダーでよい。成形されたばかりの、伸長されていない形状では、連続的な第一表面は、すべての側面で約１ｍｍ間隔で配置された１ｍｍ平方の液体透過性開口部の規則的なパターンを全体的に形成した。二次開口部は一次開口部よりも僅かに小さく、エラストマー状ウェブに約１２〜１６％の開いた開口部区域を与える。
【０１３６】
本発明の代表的なエラストマー状ウェブは、約４００％以上までの反復する持続的なウェブ伸長により、ウェブの弾性または多孔度に重大な影響を及ぼすことなく、信頼性のある弾性性能を示した。一般的に、ウェブは、表皮層が非弾性ひずみを経験するので、最初の伸長でより高いモジュラスを示した。その後、非弾性表皮層ひずみの区域で相互接続部材上に微視的なしわが形成され、これによってより低く、一般的に一定したウェブモジュラスが生じたと考えられる。
【０１３７】

試料１ａは組成物１の押出単層エラストマー状フィルムであり、試料１ｂは、中央層として組成物１および中央層の対向する表面上に配置された表皮層としてポリエチレンを有する共押出した多層フィルムであり、試料１ｃは、多層共押出フィルム１ｂから上記の方法により形成した立体的なエラストマー状ウェブである。
【０１３８】
本説明全体を通して記載したすべての特許、特許出願（およびそれに対して公布される特許、並びに対応して公開される外国特許出願すべて）、および文献をここに参考として含める。しかし、ここに参考として含める文書のどれも本発明を開示または記載しているとは認められない。
【０１３９】
本発明の特定の実施態様を例示し、説明したが、当業者には明らかな様に、本発明の精神および範囲から離れることなく、様々な他の変形および修正が可能である。従って、請求項は、本発明の範囲内に入るその様な変形および修正をすべて含むものとする。
【図面の簡単な説明】
【図１】 共に譲渡された米国特許第４，３４２，３１４号に一般的に開示されている型の、先行技術の重合体状ウェブを示す拡大した、部分的な透視図である。
【図２】 本発明の、２層の重合体フィルムを有し、その少なくとも一方がエラストマー状である、好ましいエラストマー状ウェブを示す拡大した、部分的な透視図である。
【図３】 図２に一般的に示す型のウェブを示す別の拡大した部分図であるが、本発明の別のエラストマー状ウェブのウェブ構造をより詳細に示す。
【図４】 本発明の、２個の表皮層間にエラストマー層を配置した、エラストマー状ウェブの好ましい多層フィルムの拡大断面図である。
【図５】 本発明の別のエラストマー状ウェブの、第一表面の平面に投影した開口部形状の平面図である。
【図６】 図５の区分線６−６に沿って見た相互接続部材の拡大断面図である。
【図７】 図５の区分線７−７に沿って見た相互接続部材の別の拡大断面図である。
【図８Ａ】 様々な伸長状態にある本発明のエラストマー状ウェブの開口部の断面を図式的に示す図である。
【図８Ｂ】 様々な伸長状態にある本発明のエラストマー状ウェブの開口部の断面を図式的に示す図である。
【図８Ｃ】 様々な伸長状態にある本発明のエラストマー状ウェブの開口部の断面を図式的に示す図である。
【図９】 約１ｍｍ平方開口部の規則的なパターンを有する本発明のエラストマー状ウェブの第一表面を示す拡大光学顕微鏡写真である。
【図１０】 図９に示すエラストマー状ウェブの、伸長していない状態にある第二表面を示す拡大走査電子顕微鏡写真の透視図である。
【図１１】 図９に示すエラストマー状ウェブの、約１００％伸長した状態の、第二表面を示す拡大走査電子顕微鏡写真の透視図である。
【図１２】 本発明のエラストマー状ウェブの開口部の、伸長および回復後に形成されたしわを示す、拡大走査電子顕微鏡写真の透視図である。
【図１３】 本発明のエラストマー状ウェブを含んでなる使い捨て衣類の部分的に切り取った透視図である。
【図１４】 使い捨て衣類用サイドパネルの好ましい実施態様の、簡素化し、部分的に切り取って示す図である。
【図１５】 図２に示すウェブ構造の形成に一般的に有用なラミネート構造を示す、簡素化した、部分的に分解した透視図である。
【図１６】 図１５に一般的に示す型の平らなラミネート構造を所望の曲率半径にロール巻きし、その末端同士を接合することにより形成した管状部材の透視図である。
【図１７】 本発明に一般的に従うエラストマー状フィルムをデボス加工および孔開けするのに好ましい方法および装置を図式的に示す簡素化した図である。
【図１８】 本発明の別のエラストマー状ウェブを示す拡大した、部分的に切り取った透視図である。
【図１９】 図１８の区分線１９−１９に沿って見た、ウェブの拡大断面図である。[0001]
Field of Invention
The present invention relates to a low stress relaxation elastomeric material suitable for use in a macroscopically expanded, three-dimensional porous polymeric web.
[0002]
Background of the Invention
In the field of disposable absorbent products, absorbent devices such as disposable diapers with fasteners, pants-type diapers, training pants, sanitary napkins, panty liners, incontinence briefs, etc. are constructed of elastic materials, size ranges, exercises It is known to improve ease and compatibility over time. Also, especially in products that are worn under hot and humid conditions, provide sufficient porosity in all areas of the product that can cause skin irritation and thermal rashes due to excessive occlusion of the skin It is well known that this is preferable. The nature of many disposable absorbent products is likely to cause skin irritation because moisture or bodily effluent is trapped between the elasticized portion of the product and the wearer's skin. The elasticized portion of the disposable product is particularly prone to skin irritation because it is more prone to stick to the body and thus often occludes the area of skin for a long time. Various methods for imparting elasticity to a polymer film are known in the art. The better the health care or personal hygiene product fits the body with a highly elastic material, the less air flow to the skin and the vapor flow from the blocked area. Respirability (especially vapor permeability) has become more important for skin hygiene. Various methods for imparting porosity to polymer films and improving breathability are also known in the art, but have long been used in personal hygiene or health care products, especially disposable products, bandages, wraps and dressings. There remains a need for polymeric films or webs with both sufficient elasticity and porosity that are suitable for continuous use.
[0003]
Disposable diapers and other absorbent products with elasticized leg cuffs or elasticized waistbands to provide a more comfortable fit and more effectively prevent leakage It is well known. Elasticity is often achieved by heat treatment of a polymeric material that provides the desired shearing or gathering of a portion of the diaper. One such method is described in US Pat. No. 4,681,580, issued July 21, 1987 to Reising et al., Which is hereby incorporated by reference. Other methods of imparting elasticity are all disclosed in US Pat. No. 5,143,679, published September 1, 1992 to Weber et al., 5,156,793, 1992 10 No. 5,167,897, published Dec. 1, 1992 to Weber et al.
[0004]
Several means are known in the art for making elastically flat polymer films more porous, such as die stamping, slitting, and hot-pin melt drilling. However, when any of the above techniques is applied to a thermoplastic elastomeric film, the degree of reliable elastic performance decreases with increasing porosity. For example, when a circular hole is drilled in a flat film, the applied stress S₁In contrast, the local stress S perpendicular to the stress applied around the hole₂Occurs. This local stress S₂Is S₁It is larger and approaches 3 times the applied stress. For non-circular holes, the stress concentration can be even greater. As a result, the edges of the material form the edges of the holes in the stressed plane, so the holes are the source of tear initiation points at those edges. In typical thermoplastic elastic films, such holes tend to initiate tearing and can spread over time to catastrophic failure of the film. When used on an elasticizing part of a disposable absorbent product, this breakage loses important elastic properties including the comfort, fit and use of the absorbent product.
[0005]
Prior art web structures that provide sufficient porosity preferred for use as a contact surface with the wearer on a disposable absorbent product are two fundamentally different materials, i.e. inherently liquid permeable structures, e.g. Fibrous nonwoven material, and liquid impervious material, such as a polymeric web, the impervious material provides a certain degree of permeability by perforation, through which liquid and moisture pass It is designed to flow. Neither material is characteristically elastic, and as a result both are generally absorbent products in areas that require liquid permeability but do not require extensibility, such as a layer in contact with the body of a menstrual pad Used for.
[0006]
US Pat. No. 3,929,135, assigned to Thompson on Dec. 30, 1975, which is hereby incorporated by reference, proposes a porous polymer web that contacts the body suitable for disposable products. is doing. Thompson discloses a macroscopically expanded, three-dimensional topsheet comprising a liquid impermeable polymeric material. However, the polymeric material is formed to comprise a tapered capillary, the capillary being a base opening in the plane of the topsheet and an absorbent pad for use in a disposable absorbent product. It has a tip opening in intimate contact. However, the polymeric materials disclosed by Thompson are generally not elastomers, and Thompson relies on the inelastic properties of thermoformed monolayer films to produce the desired steric structure.
[0007]
Still other materials that are used as surfaces in contact with the body in the field of disposable absorbent products are incorporated herein by reference, co-assigned U.S. Pat. No. 4,342,314, on Aug. 3, 1982. It is described in Radel et al. The Radel et al. Patent is an improved, comprising a regular continuum of a capillary network originating from one surface of a web and extending in the form of an opening in the opposite surface of the web. A macroscopically expanded three-dimensional plastic web is disclosed. In a preferred embodiment, the capillary network is reduced in size in the liquid transport direction.
[0008]
The macroscopically expanded three-dimensional plastic web of the type generally disclosed in the above-assigned Thompson and Radel et al. Patents has sufficient vapor due to the porosity provided by the openings. It is very effective. However, due to material limitations, such webs generally do not have the elasticity necessary to give the resulting web superior elastomeric properties. This disadvantage greatly limits the use of such webs in the elasticizing part of absorbent products.
[0009]
Elasticized polymeric webs can be made from elastomeric materials known in the art and are described in US Pat. No. 5,501,679, promulgated on March 26, 1996 in krueger et al. It may be a laminate of polymeric materials as described. This type of laminate is generally made by coextrusion of an elastomeric material and an inelastic skin layer, followed by stretching the laminate to exceed the elastic limit of the skin layer, and then recovering the laminate. Elastomeric webs or films such as those described above can be used on parts of clothing that come into contact with the body, such as waistbands, leg covers, and side panels, but generally provide undesirable skin irritation when used for extended periods. It is not porous enough to prevent.
[0010]
Furthermore, actual use conditions for absorbent products or other personal care products typically involve heat, humidity, load and combinations thereof. Certain elastomeric materials have reduced elasticity and dimensional stability at body temperature, particularly under load or tension. Decreasing elasticity and dimensional stability will cause the absorbent product to sag and become less compatible, and in severe cases may leak from the absorbent product.
[0011]
Certain products, such as training pants, pants-type diapers, disposable diapers with fasteners, adult incontinence clothing, bandages, wraps, dressings, etc., may be of the original dimensions when the product is applied to the wearer's body. % Can be exposed to significantly greater elongation. This process further requires extensibility and recoverability of the elastomeric material.
[0012]
Because the elastomeric material is inherently tacky and extensible, the processing and handling of the elastomeric material is very difficult. Elastomeric materials tend to stick to the processing equipment and are difficult to separate from the roll or cut to the correct size for incorporation into the final product.
[0013]
It is therefore desirable to provide an elastomeric material that substantially retains elasticity under conditions where the finished product is actually used for a specific time, eg, body temperature, for about 10 hours under a sustained load.
[0014]
It would be desirable to provide an elastomeric film that conforms to shape and is breathable (ie, vapor permeable).
[0015]
More particularly, in a particularly preferred embodiment, a macroscopically expanded three-dimensional, perforated that can substantially recover its three-dimensional shape after up to about 400% strain has been applied. It is desirable to provide an elastomeric web.
[0016]
In addition, an elastomeric material suitable for use in a perforated elastomeric web designed to eliminate the effect of strain applied to the web from the edge of the hole, thereby delaying or preventing the onset of tearing. It is desirable to provide
[0017]
In addition, processability for body hygiene and health care products such as pant diapers, training pants, disposable diapers with fasteners, incontinence clothing, sanitary napkins, panty liners, dressings, bandages and wraps It would be desirable to provide an inexpensive elastomeric material with improved
[0018]
Summary of the Invention
The present invention relates to a low stress relaxation elastomeric material. This elastomeric material can be used alone or with a skin layer to form an elastomeric film. Elastomeric films are useful in the molding process to provide a porous, macroscopically expanded three-dimensional elastomeric web. In a preferred embodiment, the elastomeric web is used for elasticized or body-facing parts of disposable absorbent products or health care products such as dressings, bandages and wraps such as side panels, waistbands, covers. It is suitable for. The porous, extensible polymeric web of the present invention can also be used in other absorbent articles where a stretchable or respirable material is desired, such as a topsheet or backsheet.
[0019]
The elastomeric material of the present invention exhibits low stress relaxation, preferably at body temperature and under conditions where the load or stress is applied for a specific time. The elastomeric material exhibits low hysteresis and high elongation at break when subjected to large deformations. In a preferred embodiment, the elastomeric material is a styrene block copolymer such as polystyrene-poly (ethylene / propylene) -polystyrene (S-EP-S), polystyrene-poly (ethylene / butylene) -polystyrene (S-EB-). S), polystyrene-polybutadiene-polystyrene (S-B-S), polystyrene-polyisoprene-polystyrene (S-I-S), or hydrogenated poly (isoprene / butadiene) -polystyrene (S-IB-S), at least One vinylarene resin and a process oil, in particular a low viscosity hydrocarbon oil, such as mineral oil.
[0020]
The elastomeric material of the present invention may be in the form of a single layer film or a multilayer film comprising at least one substantially less elastic skin layer, for example a polyolefin type material including polyethylene and polypropylene. This elastomeric film is useful for forming a macroscopically expanded three-dimensional elastomeric web.
[0021]
In a preferred embodiment, the web has a continuous first surface and a discontinuous second surface spaced from the first surface. The elastomeric web exhibits a plurality of primary openings on the first surface of the web, the primary openings being limited to the plane of the first surface by a continuous network of interconnect members, and each interconnect member Has a concave cross section upward along its length. In a preferred embodiment, each interconnect member has a generally U-shaped cross section along a portion of its length, the cross section being a base generally in the plane of the first surface of the web; And a sidewall portion joined to each edge of the base and interconnected with the other sidewall portion. The interconnecting sidewall portions generally extend in the direction of the second surface of the web and are interconnected between the first and second surfaces of the web. The interconnected sidewall portions terminate substantially simultaneously with each other and form a secondary opening in the plane of the second surface of the web.
[0022]
When used as an extensible porous member in an absorbent product, the elastomeric layer of the present invention allows the interconnect member to extend in the plane of the first surface. Due to the three-dimensional nature of the web, the stress on the interconnect member in the plane of the first surface is separated from the stress at the secondary opening on the second surface and is therefore induced by potential strain at the tear initiation site. Pulled away from the stress being applied. The stress induced by the strain of the web is separated or separated from the stress induced by the strain at the secondary opening, up to about 400% or more without causing the web to break at the opening to start tearing. Since repeated and sustained web strain is tolerated, web reliability is improved.
[0023]
A method for producing an elastomeric material of the present invention, comprising providing a multilayer elastomeric film, supporting the film on a forming structure, and applying a fluid pressure differential across the thickness of the multilayer film. A method comprising the method is also provided. The fluid differential pressure is large enough to fit the multilayer film to the support structure and rupture at least a portion of the formed film.
[0024]
This specification particularly points out the subject matter of the invention in the claims and expressly claims the following, but with reference to the accompanying drawings, in which like numerals identify equivalent components, By reading the description, it is believed that the present invention can be better understood.
[0025]
Detailed Description of the Invention
As used herein, the term “comprising” means that various elements, components, or steps can be used in conjunction with the practice of the invention. Thus, the term “comprising” encompasses the more restrictive terms “consisting of” and “consisting essentially of”. As used herein, the terms “elastic” or “elastomeric” can be stretched or deformed under externally applied force and, after the external force is released, its original size or shape substantially This applies to all materials that recover spontaneously and persist only in small amounts (typically about 20% or less) of permanent set. The term “elastomer” applies to all materials exhibiting elasticity as described above.
[0026]
The term “thermoplastic” as used herein applies to all materials that can be melted and resolidified with little or no change in physical properties (degradation due to minimal oxidation is possible).
[0027]
As used herein, the term “skin layer” means a layer of a thermoplastic polymer or polymer mixture that is substantially less elastic than an elastomer layer. A skin layer is considered “substantially less elastomeric” if the permanent strain of the skin layer is at least about 20% greater than the permanent strain of the elastomer layer. Permanent set applies to the deformation of a material, measured in a sufficient amount of time after the material is released from a particular elongation until it fully recovers.
[0028]
As used herein, the term “percent elongation” refers to the length of the elastomeric material measured while the elastomeric material is stretched under an applied force and the state of the material being undeformed or unstrained. The value obtained by dividing the difference in length by the length in the undeformed state of the material and multiplying by 100. For example, the elongation of the material in an undeformed or unstrained state is 0%.
[0029]
As used herein, the term “strain” or “strain percentage” refers to a specific time (ie, 60 seconds for the test methods described herein) without fully recovering the material after the material has been released from a specific elongation. The percentage of deformation of the elastomeric material measured while in the relaxed state. The strain percentage is expressed as [(zero load elongation after one cycle−initial sample gauge length of cycle 1) / (initial sample gauge length of cycle 1)] × 100. Zero load extension means the distance between the grips at the start of the second cycle, before the load is recorded by the tensile testing device.
[0030]
As used herein, the term “stress relaxation” refers to the maximum load or force (or load or force measured at a certain initial length) encountered after stretching the elastomeric material to a predetermined length at a particular elongation rate; It means the percentage of loss of tension or load between the residual load or force measured after the sample has been held at that length or extension for a specified time. Relaxation is expressed as a percentage of the initial load loss seen at a specific elongation of the elastomeric material.
[0031]
As used herein, the term “hysteresis” refers to the difference between the energy required to stretch an elastomeric material and the energy held by the elastomeric material before shrinking from a particular stretch. The hysteresis loop is completed by stretching a sample of elastomeric material to a specific length, typically 200% elongation, and returning to zero load.
Other terms are defined when first described.
[0032]
FIG. 1 illustrates a prior art macroscopically inflated, three-dimensional, fibrous, liquid permeable that is well suited for use as a topsheet in disposable absorbent products such as diapers and sanitary napkins. FIG. 3 is an enlarged, partially cutaway, perspective view of the polymeric web 40 of FIG. The prior art web is generally consistent with the disclosure of co-assigned U.S. Pat. No. 4,342,314, promulgated to Radel et al. On August 3, 1982, which is incorporated herein by reference. . The liquid permeable web 40 includes a plurality of openings, eg, a plurality of fibrous elements connected to each other, eg, a plurality of fibrous elements 42, 43, 44, 45, and 46 connected to each other at the first surface 50 of the web. The opening 41 formed by is shown. Each fibrous element comprises a base portion 51, for example a base portion 51 located in the plane 52 of the first surface 50. Each base portion has a side wall portion, such as a side wall portion 53, attached to its respective edge. The side wall portion generally extends in the direction of the second surface 55 of the web. The intersecting sidewall portions of the fibrous elements are connected to each other in the middle of the first and second surfaces of the web and terminate substantially simultaneously with each other in the plane 56 of the second surface 55.
[0033]
In a preferred embodiment, the base 51 is a microscopic view of surface deformation generally in accordance with the disclosure of U.S. Pat. No. 4,463,045, issued July 31, 1984 to Ahr et al., Which is hereby incorporated by reference. A typical pattern 58. The micro-pattern 58 of surface deformation makes it possible to see a substantially non-glossy surface when the incident light glands hit the web.
[0034]
In another embodiment, the prior art web is a web as described in U.S. Pat. No. 4,637,819 to Ouellette et al., Promulgated January 20, 1987, which is hereby incorporated by reference. The first surface 50 can include a number of much smaller capillary network structures (not shown). Because the smaller liquid-treated capillary network makes it more porous, the web of the present invention is believed to function more efficiently when used as an extensible porous portion of a disposable absorbent product.
[0035]
As used herein, the term “interconnect member” refers to a part or all of an element of an elastomeric web that partially defines a primary opening by a continuous network structure. Exemplary interconnect members include the Radel et al. '314 patent mentioned above and US Pat. No. 5,514,105, 1996 to Goodman, Jr., et al., Both of which are hereby incorporated by reference. May 7, 2018, but is not limited to these. As will be apparent from the following description and drawings, the interconnect members are inherently continuous and are continuously interconnected to transitions that join the elements together.
[0036]
The individual interconnect members are generally described with respect to FIG. 1 as the portion of the elastomeric web that begins between the first surface 50 and extends to the second surface 55 and disposed between two adjacent primary openings. be able to. On the first surface of the web, the interconnect members collectively form a continuous network or pattern, the continuous network of the interconnect members defining the primary openings, and on the second surface of the web, The interconnect sidewalls of the interconnect members collectively form a discontinuous pattern of secondary openings.
[0037]
The term “continuous” as used herein, when used to describe the first surface of an elastomeric web, refers to the uninterrupted character of the first surface, generally in the plane of the first surface. Thus, any point on the first surface can be reached from all other points on the first surface without substantially leaving the first surface in the plane of the first surface. Similarly, the term “discontinuous” as used herein, when used to describe the second surface of an elastomeric web, generally refers to the suspended character of the second surface in the plane of the second surface. To express. Thus, no point on the second surface can be reached from all other points on the second surface without substantially leaving the second surface in the plane of the second surface.
[0038]
In general, as used herein, the term “macroscopic” refers to a structural feature or element that is readily visible to the normal naked eye when the vertical distance between the observer eye and the plane of the web is about 12 inches. apply. Conversely, the term “microscopic” applies to structural features or elements that are not readily visible to the normal naked eye when the vertical distance between the observer's eye and the plane of the web is about 12 inches.
[0039]
As used herein, the term “macro-expanded”, when used to describe a three-dimensional elastomeric web, ribbon, and film, is three-dimensional such that both surfaces of the web exhibit a three-dimensional pattern of the formed structure. This applies to elastomeric webs, ribbons and films matched to the surface of the molded structure. Such macroscopically expanded webs, ribbons and films are typically debossed (i.e., the molded structure is not formed by embossing (i.e. where the molded structure exhibits a pattern comprising predominantly male protrusions)). The pattern is made to conform to the surface of the molded structure by either extruding the resinous melt mainly when a pattern comprising a female capillary network is shown) or by extruding a resinous melt onto the surface of either mold.
[0040]
For comparison, the term “planar” when used to describe plastic webs, ribbons and films refers to the overall state of the webs, ribbons and films when viewed with the naked eye on a macroscopic scale. For example, a non-perforated extruded film or a perforated extruded film that does not exhibit significant macroscopic deformation out of the plane of the film is generally described as planar. Thus, for a perforated planar web, the edge of the material at the opening is substantially in the plane of the web, and the stress applied to the web in the plane of the web is where the tear starts at that opening. Directly tied to
[0041]
When macroscopically expanded, the elastomeric web multilayer film of the present invention is formed into a three-dimensional interconnect member that can be described as a channel. The two-dimensional cross sections of these members are disclosed as “U-shaped” as in the above-mentioned Radel et al. Patent, or more generally in the above Goodman, Jr., et al. Patent. It can be described as “concave in the upward direction”. As used herein, “upwardly concave” means that the base is generally in the first surface, the leg of the passage extends from the base to the second surface, and the opening of the passage is substantially Describes the orientation of the channel-like shape relative to the surface of the elastomeric web in the second surface. In general, as described below with respect to FIG. 5, with respect to a plane extending through the web and perpendicular to the first surface and across two adjacent primary openings, the cross-section of the interconnect member disposed therebetween is A substantially U-shaped shape that is generally concave upward is shown.
[0042]
Several means are known in the art to make a planar elasticized polymeric web without openings more porous, such as stamping, slitting, hot-pin melt opening. However, when any of the above techniques are applied to a thermoplastic elastomeric film, the elastic performance decreases with increasing porosity. When the holes are drilled in the conventional manner, the edge of the opening is in the plane of stress applied, so that when the force is applied to the web, the edge of the opening becomes the source of the tear initiation location. In a typical thermoplastic elastic film, tearing that starts at the opening due to web stress spreads over time, leading to catastrophic failure of the film. If the shape of the opening is non-circular, such as a square, rectangle, or other polygon, the stress is concentrated at the corners of the side, increasing the likelihood of tearing.
[0043]
Applicants have found in the present invention that a multilayer polymeric web comprising an elastomeric layer in combination with at least one skin layer is used and the multilayer web is macroscopically expanded by the method described herein. It has been found that by molding into a typical structure, the resulting elastomeric web exhibits superiority in high porosity and elasticity, as well as reliability and high strength.
[0044]
Preferably, the elastomer layer itself can stretch 50% to 1200% at room temperature when in a planar state with no openings. The elastomer may be a pure elastomer or a mixture with an elastomeric phase or content that still exhibits substantial elastomeric properties at ambient temperatures, including human body temperature. The elastomeric material of the present invention is a single layer film, a multilayer film comprising at least one elastomer layer, or a porous three-dimensional web produced by the method described herein, with the desired elastic and stress relaxation properties. Can be shown. Preferably, the elastomeric material has less than about 20% stress relaxation at 200% elongation at room temperature, more preferably less than about 30%, and most preferably less than about 40%. The elastomeric material of the present invention has a stress relaxation of less than about 45%, preferably less than about 50%, more preferably less than about 55% after 50% elongation at body temperature (about 100 ° F.) for 10 hours.
[0045]
The skin layer of the present invention is preferably thinner than the elastomeric layer, is significantly less elastic, and in some cases may be generally inelastic. Two or more skin layers can be used in combination with the elastomer layer of the present invention, and the skin layer generally changes the elasticity of the elastomer. If more than one skin layer is used, these skin layers can have the same or different material properties.
[0046]
FIG. 2 is an enlarged, partially cutaway, perspective view of the macroscopically expanded, three-dimensional, elastomeric web embodiment of the present invention, indicated generally as 80. The geometric structure of the liquid permeable elastomeric web 80 is generally similar to the prior art web 40 shown in FIG. 1 and generally follows the disclosure of the Radel et al. '314 patent mentioned above. . Other suitable molded film structures are disclosed in U.S. Pat. No. 3,929,135, promulgated to Thompson on Dec. 30, 1975, No. 4,324,246, Apr. 13, 1982, Mullane, et al. And No. 5,006,394, promulgated on April 9, 1991 in Baird. The disclosures of these patents are hereby incorporated by reference.
[0047]
A preferred embodiment of the elastomeric web 80 of the present invention is formed in the plane 102 of the first surface 90 by a continuous network of interconnecting members, for example interconnected members 91, 92, 93, 94, 95. A plurality of primary openings 71 are shown. The shape of the primary openings 71 projected onto the plane of the first surface 90 is preferably in the shape of a regular or irregular pattern of polygons, such as squares, hexagons, etc. In a preferred embodiment, each interconnecting member comprises a base, for example a base 81 in the plane 102, each base being a side wall portion attached to its respective edge, for example a side wall portion 83. Have. The side wall portion 83 generally extends in the direction of the second surface 85 of the web and intersects the side wall of the interconnecting member to be joined. The intersecting sidewall portions interconnect in the middle of the first and second surfaces of the web and terminate substantially simultaneously with each other, and the second opening 72 in the plane 106 of the secondary opening, eg, the second surface 85. , Form. A detailed description of a macroscopically expanded, three-dimensional elastomeric web can be found in US Patent Application No. 08 / 816,106, Mar. 14, 1997, Curro et al., The disclosure of which is incorporated herein by reference. Submitted to,
[0048]
FIG. 3 is a further enlarged partial view of a type of web generally similar to the web 80 of FIG. 2, but illustrating another web structure of the present invention. The multilayer polymeric shaped film 120 of the web 80 preferably comprises at least one elastomer layer 101 and at least one skin layer 103. FIG. 3 shows a two-layer embodiment in which the skin layer 103 is close to the first surface 90, but it is believed that there is no restriction on the layer order of the molded film 120. As shown in FIG. 3, it is presently preferred that the polymer layers terminate substantially simultaneously in the plane of the second surface, but it is not currently considered essential, ie, one or more layers are others. It can extend further toward the second surface than the other layer. The elastomeric layer comprises about 20% to about 95% of the total film thickness, and each skin layer comprises about 1% to about 40% of the total film thickness. Typically, the elastomeric film has a thickness of about 0.5 mil to about 20 mil, preferably about 1.0 mil to about 5.0 mil. Each skin layer is typically about 0.05 mils to about 5 mils thick, preferably about 0.1 mils to about 1.5 mils. In a preferred embodiment, the elastomeric layer is about 3.2 mils thick and each skin layer is about 0.15 mils thick.
[0049]
A particularly preferred multilayer polymer film 120 of the web 80 is shown in FIG. 4 in a cross section in which an elastomer layer 101 is disposed between two skin layers 103. Elastomeric layer 101 preferably comprises a thermosetting elastomer having at least one elastomeric portion and at least one thermoplastic portion. Thermoplastic elastomers typically comprise a substantially continuous amorphous matrix, interspersed entirely with glassy or crystalline areas. While not wishing to be bound by theory, the discontinuous zone acts as an effective physical bridge, whereby the material can exhibit elastic memory when it is strained and subsequently released. Conceivable. Preferred thermoplastic elastomeric materials include block copolymers and mixtures thereof. Suitable thermoplastic elastomeric materials for use in the present invention include styrene-butadiene-styrene or similar styrenic block copolymers. Certain polyolefins that exhibit the desired thermoplastic elastomer properties and consequently elasticity, such as polyethylene and polypropylene having a density of less than about 0.90 g / cc, are also suitable for use herein as thermoplastic elastomeric materials. . The skin layer preferably comprises a substantially less elastomeric material, such as a polyolefin having a density greater than about 0.90 g / cc, or other thermoplastic material. The skin layer should be in close contact with the elastomeric layer so that it does not peel completely before or after stretching the web. A material suitable for use herein as the skin layer should have the desired melt flow properties so that it can be effectively processed with the elastomeric layer to form a multilayer film. A preferred method for producing multilayer polymeric film 120 is coextrusion.
[0050]
In general, an elastomeric low stress relaxation material having desired elastic and stress relaxation properties comprises a composition comprising an elastomeric block copolymer, at least one thermoplastic polymer, and a low viscosity process oil. Can be manufactured. A preferred composition comprises about 55 wt% styrenic-olefinic triblock copolymer, about 15 wt% polystyrene, and about 30 wt% mineral oil. The composition can further include other additives such as antioxidants, anti-blocking agents and anti-slip agents. Typically, the antioxidant is no more than 1%, preferably no more than 0.5% of the total weight of the elastomeric composition.
[0051]
A number of block copolymers can be used to make the elastomeric compositions useful for making the low stress relaxation elastomeric films or sheets of the present invention. Based on the block content and the average molecular weight of the block, a linear block copolymer, such as an ABA triblock copolymer, an ABBA tetrablock copolymer, an ABAA -BA pentablock copolymer etc. are selected suitably. Such block copolymers generally comprise an elastomeric block portion B and a thermoplastic block portion A. Block copolymers suitable for use herein are thermoplastic and elastomeric. This block copolymer exhibits a glass transition temperature (T) of the thermoplastic block portion so that it exhibits elastic memory in response to external forces._g) Is generally elastomeric in the sense that it forms a generally three-dimensional, physically cross-linked or entangled structure. This block copolymer has been modified several times with end block T with little or no change in physical properties (possible minimal oxidative degradation)._gThermoplastic in the sense that it can be melted, molded and re-solidified at higher temperatures.
[0052]
In such copolymers, the block portion A is a hard block and is derived from a material having a glass transition temperature that is high enough to form a crystalline or glassy zone at the use temperature of the polymer. Such hard blocks generally entangle or agglomerate physically with other hard blocks in the copolymer. The hard block portion A generally comprises a polyvinylarene derived from styrene, α-methylstyrene, other monomers such as styrene derivatives, or mixtures thereof. The hard block portion A may be a copolymer derived from a styrenic monomer such as the above-mentioned monomer, and an olefinic monomer such as ethylene, propylene, butylene, isoprene, butadiene, and mixtures thereof.
[0053]
The hard block portion A is preferably polystyrene and has a number average molecular weight of about 1,000 to about 200,000, preferably about 2,000 to about 100,000, more preferably about 5,000 to about 60,000. It is. Typically, the hard block portion A comprises about 10% to about 80%, preferably about 20% to about 50%, more preferably about 25 to about 35% of the total weight of the copolymer.
[0054]
The material forming the B block has a sufficiently low glass transition temperature at the use temperature of the polymer so that no crystalline or vitreous zone is formed at these operating temperatures. Therefore, the B block is regarded as a soft block. The soft block portion B is typically an olefinic heavy derived from a conjugated aliphatic diene monomer containing about 4 to about 6 carbon atoms or a linear alkene monomer containing about 2 to about 6 carbon atoms. It is a coalescence. Suitable diene monomers include butadiene, isoprene, and the like. Suitable alkene monomers include ethylene, propylene, butylene, and the like. The soft block portion B preferably comprises a substantially amorphous polyolefin, such as ethylene / propylene polymer, ethylene / butylene polymer, polyisoprene, polybutadiene, etc., or mixtures thereof. The number average molecular weight of the soft block portion B is typically from about 1,000 to about 300,000, preferably from about 10,000 to about 200,000, more preferably from about 20,000 to about 100,000. Typically, the soft block portion B comprises about 20% to about 90%, preferably about 50% to about 80%, more preferably about 65 to about 75% of the total weight of the copolymer.
[0055]
A suitable block copolymer for use in the present invention comprises at least one substantially elastomeric block portion B and at least one substantially thermoplastic block portion A. The block copolymer can have a plurality of blocks. In a preferred embodiment, the block copolymer is an ABA triblock copolymer, an ABBA tetrablock copolymer, or an ABBABA block copolymer. It's okay. Also suitable for use herein are triblock copolymers having an elastomeric intermediate block B and thermoplastic end blocks A and A ′, where A and A ′ can be derived from different vinylarene monomers. . It has two or more A blocks and / or two or more B blocks, each A block can be derived from the same or different vinylarene monomers, each B block being the same or different olefin Block copolymers that can be derived from system monomers are also useful in the present invention. The block copolymer is radial, has three or more arms, each arm is B-A, B-A-B-A, and the B block is at or near the central portion of the radial polymer. It may be a polymer or a similar type of copolymer. Good results can be obtained with, for example, 4, 5, or 6 arms. The olefin block typically comprises at least about 50% by weight of the block copolymer. Unsaturation in the olefinic double bond can be selectively hydrogenated if desired, reducing sensitivity to degradation by oxidation and having a beneficial effect on elastomeric properties. For example, a polyisoprene block can be selectively reduced to form an ethylene-propylene block. The vinylarene block typically comprises at least about 10% by weight of the block copolymer. However, higher vinylarene content is more preferred for high elasticity and low stress relaxation properties.
The block copolymer may be used in the elastomeric composition of the present invention in an amount effective to achieve the desired elasticity and low stress relaxation properties. The block copolymer is typically present in the elastomeric composition from about 20 to about 80%, preferably from about 30 to about 70%, more preferably from about 40 to about 60% by weight of the elastomeric composition. , Present in the amount of.
[0056]
For use in the present invention, styrene-olefin-styrene triblock copolymers such as styrene-butadiene-styrene (S-B-S), styrene-ethylene / butylene-styrene (S-EB-S), styrene- Ethylene / propylene-styrene (S-EP-S), styrene-isoprene-styrene (S-I-S), and mixtures thereof are preferred. The block copolymer can be a single, a mixture of block copolymers, or one or more block copolymers and one or more other substantially less elastomeric polymers such as polypropylene, polyethylene, polybutadiene, It can be used in a mixture with polyisoprene, or a mixture thereof. The block copolymer used preferably contains only a small amount, and most preferably is substantially free of such other polymers.
[0057]
A particularly preferred block copolymer for use herein is a polystyrene-ethylene / butadiene-polystyrene block copolymer containing about 10% by weight excess of styrene. When the styrene content is higher, the polystyrene block portion generally has a relatively high molecular weight. Such linear block copolymers of styrene-ethylene / butadiene-styrene (S-EB-S) are commercially available from Shell Chemical Company, Huston, TX under the trade name KRATON G1600 series. Polystyrene-ethylene-ethylene / propylene-styrene (SE-EP-S) block wherein the ethylene / propylene block is derived by selective hydrogenation of unsaturation sites in a polystyrene-isoprene / butadiene-styrene block copolymer Copolymers are also preferred for use herein. Hydrogenated polystyrene-isoprene / butadiene-styrene (S-IB-S) block copolymers are commercially available from Kuraray America, Inc. New York, NY under the trade name SEPTON 4000 series. All of the styrenic-olefinic block copolymers described herein are suitable for use in low stress relaxation elastomeric materials alone or in mixtures thereof.
[0058]
Various thermoplastic or substantially less elastomeric polymers or mixtures can be used in the low stress relaxation elastomeric material of the present invention. A suitable thermoplastic polymer should preferably associate with the hard block of the block copolymer to form an intertwined steric network. While not wishing to be bound by theory, it is believed that an intertwined network structure can improve tensile, elastic and stress relaxation properties. Thermoplastic polymers such as polyphenylene oxide and vinyl arene resins derived from monomers including styrene, α-methyl styrene, other styrene derivatives, vinyl toluene, and mixtures thereof are useful in the present invention. These polymers are preferred because they are chemically compatible with the styrenic hard block of the block copolymer. It is believed that these components are advantageously compatible so that an intertwined three-dimensional network structure can be more easily formed and not physically separated from the network structure.
[0059]
The thermoplastic polymer useful here as a hard block association component should have an appropriate range of molecular weight. The thermoplastic polymers should preferably have a sufficiently high average molecular weight so that their glass transition temperature, tensile and elastic properties are increased. Also, the thermoplastic polymers useful herein should have an average molecular weight that is not significantly different from the average molecular weight of the hard block of the elastomeric block copolymer so that it is compatible with the hard block. Suitable vinylarene resins preferably have a number average molecular weight of from about 600 to about 200,000, more preferably from about 5,000 to about 150,000, and most preferably from about 10,000 to about 100,000. Polystyrene is particularly preferred. Preferred polystyrene has a number average molecular weight of about 40,000 to about 60,000 and is commercially available from Nova Chemical, Inc. Monaca, PA, under the trade name NOVACOR PS200 series.
[0060]
While not wishing to be bound by theory, polymers or resins that are generally useful as hard block associative components are “bite” into the three-dimensional network structure, giving the desired properties more than the operating temperature of the elastomeric material. It should have a high glass transition temperature (Tg). The smaller the difference between the use temperature and the glass transition temperature, the more these polymers “unwind” from the network structure and the weaker the network structure. As a result, the tensile, elastic and stress relaxation properties of the elastomeric material are adversely affected. These adverse effects are particularly significant in the stress relaxation properties.
[0061]
For body temperature applications, such as absorbent products, bandages, wraps or dressings that are worn for a long time near the human body, a polymer with a high glass transition temperature, such as polyphenylene oxide, should be used previously. It was thought. However, polyphenylene oxide has a high melting point and a relatively high melt viscosity, which makes it difficult to process. In addition, the high processing temperatures required for polyphenylene oxide may cause degradation of the elastomeric material or other components in the final product. The initial modulus of polyphenylene oxide is too high for an extensible product and requires excessive force to apply the product to the wearer.
[0062]
Since vinyl arene resins have a much lower glass transition temperature than polyphenylene oxide, they can be used in the elastomeric materials of the present invention to achieve the desired elastic and stress relaxation properties under sustained loading conditions at body temperature. It is amazing to be able to do it. In addition, since vinyl arene resins can be easily processed at relatively low temperatures, there is little or no degradation of other thermoplastic or elastomeric components.
[0063]
The vinylarene resins useful herein as polymers associated with the hard blocks preferably have a glass transition temperature of about 58 ° C. to about 180 ° C., more preferably about 70 ° C. to about 150 ° C., more preferably about 90 ° C. to about 130 ° C.
[0064]
Low molecular weight aromatic hydrocarbon resins are also useful as polymers associated with hard blocks, either alone or in a mixture with high molecular weight polyvinyl arenes, particularly polystyrene. The low molecular weight aromatic resin is preferably derived from a vinylarene monomer. Low molecular weight resins lower the viscosity and improve the processability of the elastomeric composition. While not wishing to be bound by theory, it is believed that low molecular weight resins tend to be less effective sterically entangled with elastomeric copolymers and polystyrene hard blocks. In addition, because of the low molecular weight, the resin can be associated with an elastomeric soft block or a thermoplastic hard block. As a result, by blending the low molecular weight resin, the percentage of the hard intertwined network structure in the composition decreases. Thus, in general, low molecular weight resins can be used as processing aids, but are believed to generally have an adverse effect on the elasticity and stress relaxation properties of films made from compositions containing these resins. It is surprising that elastomeric compositions comprising low molecular weight aromatic hydrocarbon resins, alone or in combination with polystyrene, exhibit the desired elastic and stress relaxation properties suitable for use herein. Typically, the ratio of polystyrene content to aromatic hydrocarbon resin content in the mixture is from about 1:10 to about 10: 1, preferably from about 1: 4 to about 4: 1. The number average molecular weight of the aromatic hydrocarbon resin is typically from about 600 to about 10,000. Preferred aromatic hydrocarbon resins have a glass transition temperature of about 60 ° C. to about 105 ° C. and a number average molecular weight of about 600 to about 4,000. Preferred aromatic hydrocarbon resins include ENDEX (trade name) 155 or 160, KRISTALEX (trade name) 3115 or 5140, PICCOTEX (trade name) 120 and PICCOLASTIC (trade name) D125, all commercially available from Hercules Inc, Wilmington, DE. Is mentioned.
[0065]
The thermoplastic polymer or resin mixture is generally about 3 to about 60%, preferably about 5 to about 40%, more preferably about 10 to 10% by weight of the low stress relaxation elastomeric composition used in the present invention. An amount of about 30% by weight.
[0066]
Polymers or resins associated with polystyrene, low molecular weight aromatic hydrocarbon resins, and other end blocks reduce the viscosity of the melt and improve the processability of the composition, but further reduce the viscosity and improve the processability. To increase, it has been found advantageous to add processing aids such as hydrocarbon oils. Oil lowers the viscosity of the elastomeric composition, making it easier to process the elastomeric composition. However, process oils tend to reduce the elastic retention and tensile properties of the composition. Typically, the process oil is up to about 60%, preferably from about 5 to about 60%, more preferably from about 10 to about 50%, and most preferably from about 15 to about 45% by weight of the elastomeric composition. % Present.
[0067]
In a preferred embodiment, the process oil is compatible with the composition and does not substantially degrade at the processing temperature. Suitable for use herein are hydrocarbon oils which may be linear, branched, cyclic aliphatic or aromatic. Preferably, the process oil is a white mineral oil commercially available from Witco Company, Greenwich, CT. Under the trade name BRITOL. Also preferred as process oil is another mineral oil commercially available from Pennzoil Company Penrenco Division, Karns City, PA. Under the trade name DRAKEOL.
[0068]
In general, an elastomeric composition having the desired elasticity can be produced from a composition comprising substantially only a block copolymer. However, such compositions are generally very difficult to process because the composition is highly viscous, very easy to stretch and sticky. Furthermore, the elastomeric composition is inherently tacky and difficult to handle. For example, the composition can be processed into a film, but the film tends to stick to the processing equipment and is difficult to remove from the equipment, or tends to adhere when the composition is processed and wound up It becomes very difficult to unwind for further processing into the final product.
[0069]
It has been found that mixing the pure block copolymer with other thermoplastic polymers and process oil improves the processability and handleability of the composition. Thermoplastic polymers and process oils tend to reduce the viscosity of the composition and improve the processability of the composition. To further improve the processability and handleability of the composition, particularly when such an elastomeric composition film is desired, at least one skin layer of a substantially less elastomeric material is applied to the elastomeric composition. And coextrusion. In a preferred embodiment, the elastomeric composition is co-located with the thermoplastic composition such that an elastomeric center layer is disposed between the two skin layers, each skin layer substantially joining one side of the center layer. Extrude. The two skin layers may be the same or different thermoplastic materials.
[0070]
The skin layer is at least partially compatible with the components of the elastomeric block copolymer so that there is sufficient adhesion between the central elastomeric layer and the skin layer for subsequent processing and handling, or It is preferable that they are miscible. The skin layer can comprise a thermoplastic polymer or a mixture of a thermoplastic polymer and an elastomeric polymer such that the skin layer is substantially less elastomeric than the central elastomer layer. Typically, the permanent set of the skin layer is at least about 20%, preferably at least about 30%, more preferably at least about 40% greater than the permanent set of the elastomeric center layer. Suitable thermoplastic polymers for use as the skin layer are α-alkenes including ethylene, propylene, butylene, isoprene, butadiene, 1,3-pentadiene, 1-butene, 1-hexene, and 1-octene. Polyolefins, ethylene copolymers such as ethylene-vinyl acetate copolymers (EVA), ethylene-methacrylate copolymers (EMA), and ethylene-acrylic acid copolymers derived from such monomers and mixtures of these monomers Polystyrene, poly (α-methylstyrene), styrenic random block copolymers (eg, INDEX (trade name) interpolymer commercially available from Dow Chemical, Midland, MI), polyphenylene oxide, and mixtures thereof. Furthermore, these layers can be used to enhance the adhesion between the central elastomeric layer and the thermoplastic skin layer.
[0071]
FIG. 5 is a plan view of another primary opening shape projected onto the plane of the first surface of another elastomeric web of the present invention. Although a uniform repetitive pattern is preferred, the shape of the primary openings, eg, openings 71, may generally be circular, polygonal, or mixed, and may be a regular or irregular pattern sequence. Although not shown in the figure, of course, the projected shape may be oval, teardrop shape, or other shapes, i.e., the present invention is considered to be independent of the shape of the opening.
[0072]
The interconnect elements are inherently continuous, and the uninterrupted interconnect elements interlace with each other in transition areas or portions where they are joined together, such as transition section 87 shown in FIG. Generally, the transition portion is limited by the largest circle that can be inscribed in contact with any three adjacent openings. Of course, for a particular pattern of openings, the inscribed circle of the transition portion can touch four or more adjacent openings. For illustrative purposes, the interconnect member is considered to begin or end substantially at the center of the transition portion, eg, interconnect members 97 and 98. Similarly, the side wall of the interconnect member can be described as interconnecting to the side wall of the continuous interconnect member in the area corresponding to the contact point that contacts the opening where the inscribed circle of the transition portion joins. .
[0073]
Except for the transition zone, the cross section across the center line between the beginning and end of the interconnect member is preferably generally U-shaped. However, the cross section across does not need to be uniform along the entire length of the interconnect member, and in certain opening structures it is not uniform along most of its length. For example, as can be seen from the partial view of FIG. 5, with respect to the interconnect member 96, the width dimension 86 of the base 81 can vary substantially along the length of the interconnect member. In particular, in the transition zone or portion 87, the interconnect member is melted into the continuous interconnect member, and the cross section of the transition zone or portion exhibits a substantially non-uniform U-shape, or can not see.
[0074]
While not wishing to be bound by theory, the web of the present invention is exposed to strain-induced stress due to the mechanism schematically shown in the cross-sectional views of FIGS. 8A-8C and in the micrographs 9-11. More reliable (ie resistant to catastrophic failure). FIG. 8A shows the web 80 in an unstressed state with a primary opening 71 in the plane 102 of the first surface 90 and a plane 106 of the second surface 85 away from the plane 106 of the first surface 90. A second opening 72 is shown. When the web 80 is stretched generally in the direction indicated by the arrow in FIG. 8B, the first surface 90 is pulled and the primary opening 71 is similarly pulled into the deformed structure. However, the periphery of the primary opening 71 is formed by interconnecting members on the continuous first surface. Accordingly, the opening 71 does not have an “edge” for a tear start location that sacrifices the elastic reliability of the web. The edge of the second opening 72 may be the tear initiation location, but due to strain until the web is pulled to a point where the plane 102 does not leave the plane 106 of the first surface 90 as shown in FIG. 8C. Not subject to significant stress induced. In that planes 102 and 106 are no longer separated, the web 80 begins to behave as a substantially flat perforated web.
[0075]
It is meaningful to consider the ratio of the total web depth “D” in FIG. 8A to the film thickness “T” in FIG. 8A for an unstretched elastomeric web. The ratio D / T can be referred to as the tensile ratio and is related to the amount by which the film is pulled out of the plane of the first surface by the molding process of the present invention. Applicants generally believe that increasing the tensile ratio increases tear resistance because the second surface is located further from the first surface.
[0076]
While not wishing to be bound by theory, when the web 80 is pulled or stretched, the elastomeric layer 101 of the present invention allows the base 81 of the interconnect member forming a continuous web to be a continuous first surface. 90 is extended. The skin layer 103 helps maintain the three-dimensional nature of the web, despite the stress being applied, and prevents strain on the continuous first surface 90 and the resulting deformation of the primary opening 71. Pull at least partially away from the continuous second surface, thereby minimizing strain at the second opening 72. Thus, at least until the second opening begins to enter the plane of the first surface, the stress induced by the strain on the continuous first surface of the web is a potential potential at the tear initiation point on the discontinuous second surface. Is substantially separated from the stress induced by various strains. This stress induced by the strain of the web is substantially separated from or separated from the stress induced by the strain in the second opening, without damaging the web due to the initiation of tearing in the opening, Web reliability is significantly improved because up to 400% or more of the web is allowed to be repeated and sustained.
[0077]
The micrographs of FIGS. 9-11 are believed to visually explain the mechanism schematically shown in FIGS. FIG. 9 is an optical micrograph showing the first surface and primary opening of a web formed by the method described herein. With the just formed, unstretched structure, the continuous first surface of the web embodiment shown in FIG. 9 is generally a 1 mm square primary, spaced about 1 mm on all sides. A regular pattern of openings is formed. 10 and 11 are scanning electron micrographs showing a discontinuous second surface of the web embodiment of FIG. 9, shown on a slightly different scale. FIG. 10 shows the second surface of the elastomeric web in a generally unstretched state in a plane far from the plane of the first surface. FIG. 11 shows the second surface of the web in an approximately 100% stretched state. As shown in FIG. 11, the edge of the second opening remains away from the plane of the first surface. Some distortion of the second opening has occurred, but the edge is substantially unstressed. Again, web reliability is significantly improved because the stress induced by the strain of the web is substantially separated from the stress induced by the strain at the second opening.
[0078]
The specific elastic behavior of a flat multilayer film or fiber having a skin layer with relatively low elasticity, stretched beyond the elastic limit, is described in the above U.S. patent to Krueger et al., As well as to Swenson et al. As described in US Pat. No. 5,376,430, issued Dec. 27, 1994, and 5,352,518 to Muramoto et al., Issued Oct. 4, 1994. Known in the art. As shown in this field, the epidermis layer has microscopic peaks and valleys as it recovers after stretching beyond the elastic limit of the epidermis layer, because the surface area of the epidermis layer increases relative to the elastomeric layer. May form irregular microstructures.
[0079]
Similarly, when the web of the present invention is first stretched, the stretched skin layer may be stressed beyond its elastic limit. The elastomer layer allows the web to return to its macroscopic and three-dimensional structure before it is stressed, but the part of the skin layer that is stressed beyond the elastic limit is the excess created by inelastic stretching. Because of the material, it may not return to its pre-stressed structure. By recovering after stretching, the epidermis layer forms irregular microstructures of microscopic peaks and valleys, more generally lateral wrinkles as shown in the micrograph of FIG. The wrinkles occur on the interconnect member in a substantially uniform pattern, generally across the direction of extension, and are generally arranged radially around the primary opening. Depending on the extent of elongation to the web, the wrinkles may be substantially confined to the continuous first surface of the web, or more generally, may extend over substantially the entire surface of the interconnect member.
[0080]
Without being bound by theory, laterally extending wrinkles are considered advantageous for elastomeric webs for at least two reasons. First, wrinkles give the elastomeric web a softer overall structure or feel. Secondly, wrinkles that are arranged radially around the primary opening and extend towards the second opening give better liquid handling properties when used as a body-contacting web of disposable absorbent products. Can do.
[0081]
An exemplary embodiment of an elastomeric web of the present invention used in a disposable absorbent product in the form of a diaper 400 is shown in FIG. As used herein, the term “diaper” means a garment commonly worn by infants and incontinent persons and worn around the lower body of the wearer. However, the elastomeric web of the present invention can also be applied to other absorbent products such as incontinence briefs, training pants, sanitary napkins and the like. The diaper 400 shown in FIG. 13 is a simplified absorbent product that shows the diaper prior to application to the wearer. However, of course, the present invention is not limited to the specific type or shape of the diaper shown in FIG. A particularly preferred exemplary embodiment of a disposable absorbent product in the form of a diaper is disclosed in Buell et al., US Pat. No. 5,151,092, promulgated on 29 September 1992, which is hereby incorporated by reference. ing.
[0082]
FIG. 13 is a perspective view showing the structure of the diaper 400 by cutting away a part of the structure, showing a state in which the diaper 400 is not contracted (that is, all contractions induced by elasticity are removed). The part of the diaper 400 that comes into contact with the wearer is visible. The diaper 400 shown in FIG. 13 includes a liquid permeable top sheet 404, a liquid impermeable back sheet 402 joined to the top sheet 404, and an absorbent core 406 disposed between the top sheet 404 and the back sheet 402. Become. Other structural features can also be included, such as elastic leg coverings and securing means for securing the diaper in place on the wearer.
[0083]
The topsheet 404, the backsheet 402, and the absorbent core 406 can be assembled in a variety of well-known arrangements, and preferred diaper structures are each included as a “shrinkable side for disposable diapers”. U.S. Pat. No. 3,860,003, Kenneth B. Buell, issued January 14, 1975, 5,151,092, Buell, issued September 9, 1992, and 5,221, No. 274, Buell promulgated June 22, 1993, and US Pat. No. 5,554,145 entitled “Absorbent Product with Stretching Waist Portion of Multi-zone Structural Elastic Film Web”, Roe et published on September 10, 1996, US Pat. No. 5,569,234 entitled “Disposable Pull-on Pants”, Buell et al. on October 29, 1996, “ US Pat. No. 5,580,411 entitled “Zero Scrap Method for Manufacturing Side Panels for Highly Harvesting Products”, issued to Nease et al. On Dec. 3, 1996, and “Multi-directional Stretchable Side Panels” US patent application Ser. No. 08 / 915,471, filed Aug. 20, 1997, in the name of Roble et al.
[0084]
FIG. 13 shows an exemplary embodiment of a diaper 400 in which the topsheet 404 and the backsheet 402 can be stretched together and have a length and width dimensions that are generally larger than the dimensions of the absorbent core 406. The top sheet 404 is overlapped with and joined to the back sheet 402 to form the peripheral part of the diaper 400. The peripheral part limits the outer periphery or edge of the diaper 400. The perimeter comprises a distal edge 401 and a longitudinal edge 403.
[0085]
The size of the backsheet 402 is determined by the size of the absorbent core 406 and the exact diaper design selected. In a preferred embodiment, the backsheet 402 has a deformed hourglass shape and is at least about 1.3 centimeters to about 2.5 centimeters (about about the entire periphery of the diaper beyond the absorbent core 406). 0.5 to about 1.0 inch).
[0086]
The topsheet 404 and the backsheet 402 are joined in any suitable manner. As used herein, the term “join” refers to a structure in which the top sheet 404 is directly joined to the back sheet 402 by fixing the top sheet 404 directly to the back sheet 402, and the top sheet 404 is secured to the intermediate member. A structure in which the top sheet 404 is indirectly joined to the back sheet 402 by fixing the intermediate member to the back sheet 402 is included. In a preferred embodiment, the topsheet 404 and the backsheet 402 are secured directly to each other at the periphery of the diaper by attachment means (not shown), such as adhesive or other attachment means known in the art. The For example, the topsheet 404 can be secured to the backsheet 402 using a uniform continuous layer of adhesive, a patterned layer of adhesive, or a series of separate lines or points of adhesive.
[0087]
The distal edge 401 forms a waist region, which in a preferred embodiment comprises a pair of elastomeric side panels 420 that are transverse to the distal edge 401 of the diaper 400 in the unfolded structure. Is growing. In a preferred embodiment, the elastomeric side panel 420 comprises the elastomeric web of the present invention. In a particularly preferred embodiment, when used as an elastomeric side panel, the web of the present invention is further processed to form a composite laminate and the web is placed on one side of the web by methods known in the art, such as adhesive bonding. Adhere to the fibrous nonwoven material, preferably on both sides, to form a soft, supple elastic part.
[0088]
Suitable fibrous nonwoven materials for use in the composite laminates of the present invention are synthetic fibers (eg, polypropylene, polyester, or polyethylene), natural fibers (eg, wood, cotton, or rayon), or natural and synthetic fibers. Includes nonwoven webs formed from the combination. Suitable nonwoven materials can be formed by a variety of manufacturing methods such as cursing, spun-bonding, hydro-entangling, and other methods known to those skilled in the art of nonwoven materials. The presently preferred fibrous material is a carded polypropylene, commercially available from Fiberweb, Simpsonville, S.C.
[0089]
The fibrous nonwoven material can be bonded to the elastomeric web by any of a variety of methods known in the art. Suitable bonding methods include, for example, adhesive bonding, such as using a uniform continuous layer of adhesive, a patterned layer of adhesive, or a line of separate lines, spirals, or points of adhesive, or Thermal bonding, pressure bonding, ultrasonic bonding, dynamic mechanical bonding, or other suitable attachment means known in the art or a combination of these attachment means may be mentioned. An exemplary bonding method is described in U.S. Pat. No. 5,099, entitled “Absorptive product with non-woven perforated film cover sheet” by Aziz et al. S. SIR No. H1670, published July 1, 1997.
[0090]
After being bonded to the fibrous nonwoven material, the composite web tends to be less elastomeric due to the relatively low elasticity of the bonded nonwoven material. To make the nonwoven material more elastic and to restore elasticity to the composite laminate, the above-mentioned Buell et al. '092 patent, as well as the above Weber et al.' 897, Buell et al. '793, And the method and apparatus used to impart elasticity to "zero strain" laminates by progressive stretching, as described in the '679 patent of Weber et al. The resulting elasticized “zero strain” composite web is an absorbent garment that provides a soft fabric-like feel and comfortable fit for extended use.
[0091]
Side panel 420 can be joined to the diaper in any suitable manner known in the art. For example, as shown in FIG. 13, the side panel 420 is secured directly to the backsheet 402 by attachment means (not shown) such as adhesive or any other attachment means known in the art. be able to. A particularly preferred structure for the side panel 420 is shown in FIG. 14, which structure was promulgated to LaVon et al. On September 23, 1997 and assigned to US 08 / 155,048, filed November 19, 1993, by Roles et al., Described in greater detail, the disclosures of both of which are incorporated herein by reference.
[0092]
As shown in FIG. 14, the side panel 420 preferably comprises two webs or strips 421 and 422. Strips 421 and 422 may be two separate strips, or these strips may be folded from a single strip at the leading edge 424 and the lengths of the two strips obtained in parallel. It can be formed by shifting so as not to occur. If two separate strips are used, a suitable adhesive can be used to adhere to each other at the leading edge 424 and simultaneously to the tape tab 423. The side panel 420 can be bonded to the backsheet 402 at any bonding area 425 in any suitable manner, particularly as disclosed in the LaVon et al. The side panel pairs need not be identical, but are preferably mirror images of each other. Another example of a diaper having elasticized side panels is US Pat. No. 4,857,067 entitled “Disposable Diapers with Sheared Ears”, each of which is incorporated herein by reference, on August 15, 1989. Promulgated by Wood et al., No. 4,381,781, promulgated by Sciaraffa, et al. On May 3, 1983, No. 4,938,753, Van Gompel, et al. By July 3, 1990 No. 5,151,092, promulgated to Buell on September 9, 1992, and No. 5,221,274 to Buell on June 22, 1993, “Dynamic compatibility” No. 5,669,897, promulgated to LaVon, et al. On September 23, 1997, No. 5,897,545, April 27, 1999 to Kline, et promulgated in al., "with side panels that can be extended in multiple directions No. 08 / 155,048 entitled “Absorptive Products”, filed November 19, 1993 in the name of Roble et al.
[0093]
The diaper 400 can also include a securing mechanism 423. The securing mechanism 423 preferably maintains the waist region 401 in an overlapping structure, provides lateral tension around the diaper 400, and holds the diaper 400 on the wearer. The securing mechanism 423 preferably comprises tape tabs and / or hook and loop securing components, although all other known securing means can generally be used. A typical fastening mechanism is US Pat. No. 3,848,594 entitled “Tape Fastening Mechanism for Disposable Diapers”, promulgated to Buell on November 19, 1974, and US Pat. No. 4 entitled “Absorbent Product”. , 662,875, issued May 5, 1987 to Hirotsu et al., U.S. Pat. No. 4,846,815 entitled "Disposable Diaper with Improved Fixing Device", July 11, 1989. US Patent No. 4,894,060 entitled "Disposable Diaper with Improved Hook Fastener Part", promulgated to Nestegard on January 16, 1990, "Pressure Sensitive Adhesive Fixture and its Production U.S. Pat. No. 4,946,527 entitled "Method", promulgated to Battrell on August 7, 1990, and U.S. Pat. No. 5,151,092, promulgated to Buell on September 9, 1992, and Rice Pat. No. 5,221,274, are described in the promulgation, to Buell on June 22, 1993. The securing mechanism may also provide a means for holding the product in a discarded configuration, as described in US Pat. No. 4,963,140, promulgated by Robertson on October 16, 1990. The locking mechanism reduces the displacement of the overlapping portions as described in US Pat. No. 4,699,622, or US Pat. Nos. 5,242,436, 5,499,978, Primary and secondary locking mechanisms for improving compatibility as described in US Pat. Nos. 5,507,736 and 5,591,152 can also be included. Each of these patents is hereby incorporated by reference. In another embodiment, opposing sides of the garment can be joined or welded to form a pant. This allows the product to be used as a pant diaper or training pant.
[0094]
Other elastic members (not shown) of the present invention can be disposed adjacent to the periphery of the diaper 400. The elastic member is preferably along each longitudinal edge 403 so that the elastic member pulls and holds the diaper 400 against the wearer's leg. Further, an elastic member can be placed adjacent to one or both of the distal edges 401 of the diaper 400 to provide a waistband with or without a leg covering. For example, suitable waistbands are described in US Pat. No. 4,515,595 to Kievit et al., Issued May 7, 1985, the disclosure of which is hereby incorporated by reference. Further, a method and apparatus suitable for manufacturing disposable diapers having elastic members that are elastically stretchable is disclosed in U.S. Pat. No. 4,081,301 to Buell, 1978, the disclosure of which is incorporated herein by reference. It is described in the promulgation on March 28.
[0095]
The elastic member is an ordinary unconstrained structure, and is fixed to the diaper 400 in a state where it can be elastically contracted so that the elastic member effectively contracts or draws the diaper 400. The elastic member can be fixed in an elastically contractible state by at least two methods. For example, the elastic member can be extended and fixed while the diaper 400 is not contracted. Further, for example, the diaper 400 can be contracted by attaching a pleat, and the elastic member can be fixed and connected to the diaper 400 while the elastic member is in a relaxed or non-extended state. The elastic member can extend along a portion of the length of the diaper 400. Alternatively, the elastic member can extend along the entire length of the diaper 400, or along any other length suitable to provide a line that can be elastically contracted. The length of the elastic member is determined by the design of the diaper.
[0096]
The elastic member may have any structure. For example, the width of the elastic member can vary from about 0.25 millimeters (0.01 inches) to about 25 millimeters (1.0 inches) or more, and the elastic members comprise a single strand of elastic material? Or may comprise several parallel or non-parallel strands of elastic material, or the elastic member may be rectangular or curvilinear. Further, the elastic member can be secured to the diaper by any of several methods known in the art. For example, various bonding patterns can be used to ultrasonically bond the elastic member to the diaper 400, seal with heat and pressure, or simply glue the elastic member to the diaper 400.
[0097]
As shown in FIG. 13, the absorbent core 406 preferably includes a liquid distribution member 408. In a preferred structure, such as that shown in FIG. 13, the absorbent core 406 is in fluid communication with the liquid distribution member 408 and includes an acquisition layer or member 410 disposed between the liquid distribution member 408 and the topsheet 404. The acquisition layer or member 410 includes several fibers including synthetic fibers including polyester, polypropylene, or polyethylene, natural fibers including cotton or cellulose, mixtures of such fibers, non-woven or woven webs. It comprises different materials, or equivalent materials or combinations of such materials.
[0098]
In use, the back waistband area is placed under the wearer's waist and the rest of the diaper 400 is pulled between the wearer's legs so that the front waistband area is placed in front of the wearer. As a result, 400 is attached to the wearer. The elastomeric side panels are then stretched as necessary to comfortably fit, and a tape tab or other fastener is preferably secured to the area facing the outside of the diaper 400. By having the side panel 420 comprising the elastomeric web of the present invention, the diaper can be used in a manner that allows it to fit, comfortably fit and breathe on children of various sizes.
[0099]
Although a disposable diaper has been shown as a preferred embodiment of a garment comprising the elastomeric web of the present invention, the present disclosure is not limited to a disposable diaper. Other disposable garments can also incorporate the elastomeric web of the present invention into various parts to add comfort, suitability and breathability. It is also believed that durable garments such as underwear and swimwear can effectively utilize the durable, porous and extensible features of the elastomeric web of the present invention.
[0100]
The multilayer film 120 of the present invention can be processed using conventional procedures for manufacturing multilayer films with conventional coextruded film manufacturing equipment. In general, polymers are produced using a cast or blown film extrusion process, both described in "Plastics Extrusion Technology" 2nd Ed. By Allan A. Griff (Van Nostrand Reinhold-1976), which is hereby incorporated by reference. Can be melt processed into a film. The cast film is extruded through a linear slot die. In general, a flat web is cooled on a large rotating, polished metal roll. The web cools rapidly, is peeled off from the first roll, passes over one or more auxiliary rolls, then passes through a series of rubber-coated take-off or “spin” rolls and is finally sent to a winder.
[0101]
In blow molded film extrusion, the melt is extruded upward through a thin annular die opening. This process is also called tubular film extrusion. Air is introduced through the center of the die to inflate and inflate the tube. Bubbles that move are formed in this way, and are maintained at a constant size by adjusting the internal air pressure. The film tube is cooled by air blown through one or more cooling rings surrounding the tube. The film is then flattened by drawing the tube through a pair of take-up rolls into a flattened frame and sent to a winder.
[0102]
The coextrusion process requires two or more extruders and a coextrusion feed block or multi-manifold die mechanism or a combination of the two to achieve a multilayer film structure. U.S. Pat. Nos. 4,152,387 and 4,197,069 to Cloeren, both issued May 1, 1979 and April 8, 1980, respectively, which are incorporated herein by reference, are co-extruded The supply block principle is disclosed. Multiple extruders are connected to the supply block, which uses a movable flow divider to change the flow path geometry in direct proportion to the volume of polymer passing through the individual flow paths. Let The flow paths are designed so that at their confluence, the materials flow together at the same flow rate and pressure, eliminating interfacial stresses and flow instabilities. As the material merges in the supply block, the material flows into the single manifold die as a composite structure. In such a production process, it is important that the difference in melt viscosity and melt temperature of the material is not so great. Otherwise, the flow in the die becomes unstable and the layer thickness distribution in the multilayer film becomes difficult to control.
[0103]
Alternative methods for feed block coextrusion are described in US Pat. Nos. 4,152,387, 4,197,069, and 4,533,308, incorporated herein by reference, on August 6, 1985. Multi-manifold or vane die as described in Cloeren promulgated. In the feed block mechanism, the melt streams merge outside before entering the die body, whereas in multi-manifold or wing dies, each melt stream has its own manifold in the die, where the polymer is in each manifold. Spread independently. The melt stream is intimately mixed with each melt stream and the full width of the die near the die exit. The moveable wing adjusts the outlet of each channel in direct proportion to the volume of material flowing therethrough so that the melt flows together at the same linear flow rate, pressure and desired width.
[0104]
There are several advantages to using a blade die because the melt flow properties and melting temperature of the polymer vary over a wide range. Because the die itself can be thermally isolated, different polymers can be treated together, with high melting temperatures, for example up to 175 ° F. (80 ° C.).
[0105]
Each manifold in the wing die can be designed and fabricated specifically for a specific polymer. Thus, the flow of each polymer is only affected by its manifold design, not the force exerted by multiple polymers. This allows materials with significantly different melt viscosities to be coextruded into a multilayer film. In addition, the wing die can accommodate the width of the individual manifold, so that the inner layer is completely surrounded by the outer layer, leaving no exposed edges. The above patent also discloses a method of combining a supply block mechanism and a wing die to achieve a more complex multilayer structure.
[0106]
The multilayer film of the present invention comprises two or more layers, and at least one of the layers can be made elastomeric. It is also conceivable to use a plurality of elastomers and join each elastomer layer to one or two skin layers. In a three-layer film, the core layer 101 has opposing first and second sides, one side bonded to one side of each outer skin layer 103 substantially continuously before stressing the web. Is done. A three-layer film, such as the multilayer film 120 shown in FIG. 4, preferably comprises a central elastomeric core 101 that can account for about 10-90% of the total film thickness. The outer skin layer 103 is generally the same (although this is not necessary) and can account for about 5 to 45% of the total film thickness. The elastomeric layer is generally substantially bonded to one or two skin layers without the use of an adhesive, but an adhesive or tie layer can be used to enhance the adhesion between the layers. When used, each tie layer may occupy about 5-10% of the total film thickness.
[0107]
After the co-extrusion of the multilayer elastomeric film, it is preferably fed into a forming structure and drilled and allowed to cool, thereby producing the macroscopically expanded, three-dimensional, porous elastomeric web of the present invention. In general, the film can be formed by vacuuming such a film against a forming screen or other forming structure and passing a stream of air or water over a surface that faces the outside of the film. it can. Such a process is described in the above-mentioned Radel et al. Patent, which is hereby incorporated by reference, as well as in U.S. Pat. No. 4,154,240, promulgated in Lucas et al. Alternatively, the formation of a three-dimensional elastomeric web can be achieved by applying a liquid stream as described in commonly assigned US Pat. No. 4,695,422, promulgated in Curro et al. It can also be achieved by acting with sufficient force and mass flux to cause web formation. Alternatively, films can be formed as described in commonly assigned US Pat. No. 4,552,709 to Koger et al., Which is hereby incorporated by reference. Preferably, the molding structure is incorporated as disclosed in U.S. Pat. Nos. 4,878,825 and 4,741,877, both of which are incorporated herein by reference and assigned to Mullane, Jr. The elastomeric web is uniformly macroscopically expanded and perforated by a method that supports the fluid pressure differential area.
[0108]
Although not shown in the figures, the method of the present invention using a conventional molded screen having a woven wire support structure also forms a web that falls within the scope of the present invention. The wire intersections of the woven wire forming screen produce a macroscopically expanded three-dimensional web having a corrugated pattern on the first surface, the corrugations corresponding to the wire intersections of the screen. However, the corrugations remain in the plane of the first surface, generally away from the plane of the second surface. The cross-section of the interconnect member remains generally concave in the upward direction, and the end of the interconnect side wall of the interconnect member forms a secondary opening substantially in the plane of the second surface.
[0109]
A particularly preferred forming structure comprises a photo-etched laminate structure as shown in FIG. 15, which shows a photo-etched laminate structure of the type used to form a plastic web of the type generally shown in FIG. Figure 2 shows an enlarged, partially separated perspective view. Laminate structure 30 is preferably constructed in accordance with the disclosure of the Radel et al. Patent mentioned above and comprises individual lamina 31, 32 and 33. By comparing FIG. 3 with the elastomeric web 80 shown in FIG. 2, the primary opening 71 in the plane 102 of the elastomeric web 80 is changed to the opening 61 in the top plane 62 of the photoetched laminate structure 30. It turns out that it corresponds. Similarly, the opening 72 in the plane 106 of the elastomeric web 80 corresponds to the opening 63 in the lowest plane 64 of the photoetched laminate structure 30.
[0110]
The uppermost surface of the photo-etched laminate structure 30 located in the uppermost plane 62 can have a microscopic pattern of protrusions 48 without departing from the scope of the present invention. This can preferably be achieved by applying a resist paint corresponding to the desired microscopic pattern of surface deformation to the top of the flat photoetched thin layer 31 and then starting a second photoetching step. The second photoetching process forms a thin layer 31 having a microscopic pattern of protrusions 48 on the uppermost surface of the interconnect element that defines the pentagonal opening, eg, opening 41. The microscopic pattern of protrusions does not substantially remove the first surface from the plane of the first surface. The first surface is recognized on a macroscopic scale and the protrusion is recognized on a microscopic scale. The construction of a laminate structure having such a pattern of protrusions 48 on the top layer is generally disclosed in the above-mentioned Ahr et al. Patent.
[0111]
A method for constructing a laminate structure of the type generally shown in FIG. 2 is disclosed in the Radel et al. Patent mentioned above. The photo-etched laminate structure is preferably wound into a roll by conventional techniques to form a tubular molded member 520 as generally shown in FIG. 16, with the opposite ends generally following the disclosure of Radel et al. The tubular molded member 520 is manufactured by joining.
[0112]
The outermost surface 524 of the tubular molded member 520 is used to form a multilayer elastomeric web that contacts it, and the innermost surface 522 of the tubular member does not contact the plastic web during the molding operation. In a preferred embodiment of the present invention, the tubular member can be used as a molding surface on the deboss / drilling cylinder 555 in the type of process described in detail in the above-mentioned Lucas et al. Patent. A particularly preferred device 540 of the type described in that patent is shown schematically in FIG. This apparatus includes debossing and perforating means 543 and constant tension film advance and winding means 545, which winding means are optionally included in US Pat. No. 3,674,221, 1972. It is substantially the same as the corresponding part of the device disclosed in Riemersma, issued July 4, 2004, and can function substantially the same. Frames, bearings, supports, etc. that must be included with respect to the functional members of device 540 are not shown or described in detail to simplify and more clearly disclose the present invention, but such details are not It will be apparent to those skilled in the art of film processing.
[0113]
Briefly described, the apparatus 540 schematically shown in FIG. 17 continuously receives a ribbon of thermoplastic film 550 from, for example, a coextrusion apparatus 559, debosses the ribbon, and processes it into a perforated film 551. Means. Film 550 is preferably fed directly from the coextrusion process while still above its thermoplastic temperature, such that it is vacuum formed prior to cooling. Alternatively, the film 550 can be heated by blowing hot air onto one surface of the film while applying a vacuum immediately adjacent to the opposite surface of the film. In order to adequately adjust the film 550 to substantially avoid film wrinkling and / or macroscopic elongation, the device 540 is both upstream and downstream of an area where the temperature is higher than the thermoplastic temperature of the film, It comprises means for maintaining a constant machine direction tension on the film, but in that area, there is substantially no tension in the machine direction and across the machine that tends to macroscopically stretch the film. Tension is necessary to control and smooth the ribbon travel of the thermoplastic film, and the zero tension zone is derived from the film in a zone that is at a high enough temperature to deboss and punch the film. It is done.
[0114]
As shown in FIG. 17, the debossing and drilling means 543 includes a debossed drilling cylinder 555 having a closed end 580, a non-rotating triple vacuum manifold mechanism 556, and hot air to be used as desired. Includes jet means (not shown). The triple vacuum manifold mechanism 556 includes three manifolds 561, 562 and 563. FIG. 17 also shows a reed-off cooling roll 566 that is rotated by power and a soft surface roll (for example, low density neoprene) that is driven by the cooling roll. Briefly, by providing means (not shown) for independently controlling the degree of vacuum in the three vacuum manifolds, the debossing-of the film moving partially around the perforating cylinder 555 The thermoplastic ribbon is sequentially subjected to a first level vacuum with manifold 561, a second level vacuum with manifold 562, and a third level vacuum with manifold 563. As described in more detail below, the vacuum acting on the film by the manifold 561 can maintain the upstream tension in the film, and the vacuum acting by the manifold 562 can puncture the film, and the manifold 563 The vacuum acting on can cool the film to a temperature below its thermoplastic temperature and establish downstream tension therein. If desired, the film that contacts the surface of the debossing-drilling cylinder 555 is preheated by means well known in the art (and therefore not shown) before reaching the vacuum manifold 562. The plastic film comprising the flow-resistant polymer can be easily adapted during the debossing operation. The nip 570 between the cooling roll 566 and the soft surface roll 567 is loaded only on the surface, which may flatten the three-dimensional unevenness formed on the film in the above manner at high pressure. Because. However, even with the pressure on the surface at the nip 570, the vacuum exerted by the manifold 563 helps to isolate the downstream tension (ie the roll winding tension) from the debossing-debossing-drilling portion of the drilling cylinder 555. The nip 570 debossed and perforated film can be pulled away from the debossed-perforated cylinder 555. In addition, the ambient air that is aspirated by the vacuum and passes through the film and enters the manifold 563 typically cools the film to a temperature below the thermoplastic temperature and passes through the chill roll as shown by arrows 573 and 574 in FIG. Depending on the coolant, thicker films can be processed or run at higher speeds.
[0115]
The debossing and perforating means 543 is a debossing-perforating cylinder 555, means for rotating the cylinder 555 at a controlled peripheral speed (not shown), and debossing-perforating cylinder 555 so that it can rotate. A non-rotating triple vacuum manifold mechanism 556 on the inside and means for applying a regulated level of vacuum inside the three vacuum manifolds 561, 562 and 563 constituting the triple manifold mechanism 556 (not shown in the figure) And hot air jet manifold (not shown) for use if desired. The debossing-drilling cylinder 555 can be constructed in accordance generally with the disclosure of the above-mentioned Lucas et al. Patent, the perforated tubular molding surface disclosed therein being the tubular laminate molding surface of the present invention. Replace with.
[0116]
In summary, the first vacuum manifold 561 and the third vacuum manifold 563 located in the debossing-drilling cylinder 555 can maintain substantially constant upstream and downstream tension in the ribbon of the running film, respectively. The debossing-perforating cylinder 555, in the middle portion of the film adjacent to the second vacuum manifold 562, is subjected to heat and vacuum that negates tension to deboss and perforate the film.
[0117]
Although preferred uses of the disclosed photo-etched laminate structures are generally outlined in the above-assigned patent issued to Lucas et al., The photo-etched laminate structures of the present invention are It is considered that the present invention can be easily applied to directly form a three-dimensional plastic structure. In such a procedure, a heated liquid plastic material, typically a thermoplastic resin, is applied directly to the molding surface and a sufficiently large air differential pressure is applied to the heated liquid plastic material to make the material porous. Match the image of the laminate molding surface, solidify the liquid material, and then pull the three-dimensional plastic structure away from the molding surface.
[0118]
The web embodiment shown generally in FIG. 2 represents a particularly preferred embodiment of the present invention, but any number of interconnect members can be used within the web structure of the present invention, such as secondary, tertiary, etc. . An example of such a structure is shown in FIG. 18, which also shows a deformation of an interconnect member having an upwardly concave cross section. The aperture network structure shown in FIG. 18 comprises primary interconnect elements, eg, elements 302, 303, 304, and 305, interconnected by an uppermost plane 307 of the web 300, which openings are intermediate planes 314. Thus, it is further subdivided into secondary openings 310 and 311 by the secondary interconnection member 313. Primary opening 310 is further subdivided into smaller secondary openings 321 and 322 by tertiary interconnect member 320 at a lower plane 325 in web 300. As can be seen from FIG. 19 as viewed along section line 19-19 in FIG. 18, planes 314 and 325 are generally parallel to top plane 307 and bottom plane 330, and the planes thereof. Located in the middle.
[0119]
In the web embodiment shown in FIGS. 17 and 18, the primary and secondary interconnect members are further connected to an intersecting tertiary interconnect member, such as the tertiary interconnect member 320, which is connected to them. A generally concave cross-section is shown along the length of. The intersecting primary, secondary, and tertiary interconnect members each terminate substantially simultaneously at the plane 330 of the second surface 332, and a plurality of openings or windows, such as windows 370, 371, and 372, on the second surface of the web. , Form. The interconnected primary, secondary and tertiary interconnect members located between the first and second surfaces of the web 300 provide each primary opening, such as the opening 301, in the first surface 331 of the web. Obviously, it forms a closed network that connects to a plurality of secondary openings in the second surface 332 of the web, such as openings 370, 371 and 372.
[0120]
Of course, the interconnect members that are typically used in the web of the present invention and have a concave shape in the upward direction may be substantially straight along their entire length. Alternatively, these interconnect members may be curvilinear, include two or more substantially linear segments, or may be oriented in any desired direction along any portion of their length. Good. The interconnect members need not be equivalent to each other. Furthermore, the above shapes can be combined in any desired manner to form any desired pattern. Regardless of the final selected shape, the upwardly concave cross-sections that exist along the respective lengths of the interconnected interconnect members provide elastic as well as three-dimensional support to the web of the present invention.
[0121]
It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the invention. For example, if it is desired to produce a web of the present invention in which a predetermined portion of the web can prevent liquid permeation, it is advantageous to perform a debossing operation on the second surface without causing collapse of the web opening. is there. U.S. Pat. No. 4,395,215, both assigned hereto, hereby incorporated by reference, promulgated to Bishop on July 26, 1983, and U.S. Pat. No. 4,747,991, allied to 1988 5 Promulgated to Bishop on March 31, details how to build a tubular shaped structure that can produce a three-dimensionally expanded film that is uniformly debossed but has openings only in predetermined areas Is disclosed.
[0122]
With the description provided herein, it is believed that one skilled in the art can implement the present invention in many different forms. The following representative embodiments and analytical methods are described for purposes of illustrating the advantageous elastic reliability of the particularly preferred low stress relaxation elastomeric materials of the present invention.
[0123]
Test method
A. Tensile strength and elongation at break
The properties measured by this method can be correlated to the extensibility of the elastomeric film. These properties make it suitable for use in absorbent products, especially pant diapers, training pants, diapers with fasteners, or other absorbent garments that are substantially stretched when worn. Related to selection.
This test uses a tensile tester commercially available from Instron Engineering Corp., Canton, MA or SINTECH-MTS Systems Corporation, Eden Prairie, MN. The film is cut into 4 "length specimens at 1" width x CD (transverse direction at an angle of 90 ° from MD) in MD (machine direction of the film). Connect the instrument to a computer, control the test speed and other test parameters, collect, calculate and report data. The tensile stress-strain characteristics of the film are measured by ASTM method D882-83. These properties are measured at room temperature (about 20 ° C.). The procedure is as follows.
[0124]
(1) Select an appropriate grip and load cell for testing. The grip should be wide enough to mount the sample and typically uses a 1 "wide grip. The load cell has a tensile response coming from the test sample depending on the capacity or load range of the load cell used. A 50 lb load cell is typically used.
(2) Calibrate the instrument according to the manufacturer's instructions.
(3) Set the gauge length to 2 ″.
(4) Place the sample on the flat surface of the gripper according to the manufacturer's instructions.
(5) Set the crosshead speed to a constant speed of 20 "/ min.
(6) Start the test and collect data at the same time.
(7) Calculate and report tensile properties including elongation at break, loads at 100% and 200%. Report the average results of 3 samples.
[0125]
B. 2-cycle hysteresis test
The properties measured by this method are based on how the consumer feels from the side panels, waistbands, or other elastic components when the product is first used, and how Can be correlated to fit.
This test uses a tensile tester commercially available from Instron Engineering Corp., Canton, MA or SINTECH-MTS Systems Corporation, Eden Prairie, MN. The film is cut into test specimens 1 "wide x 4" long in MD. Connect the instrument to a computer, control the test speed and other test parameters, collect, calculate and report data. Two cycle hysteresis is measured at room temperature. The procedure is as follows.
[0126]
(1) Select an appropriate grip and load cell for testing. The grip should be wide enough to mount the sample and typically uses a 1 "wide grip. The load cell has a tensile response coming from the test sample depending on the capacity or load range of the load cell used. A 50 lb load cell is typically used.
(2) Calibrate the instrument according to the manufacturer's instructions.
(3) Set the gauge length to 2 ″.
(4) Place the sample on the flat surface of the gripper according to the manufacturer's instructions.
(5) Set the crosshead speed to a constant speed of 20 "/ min.
(6) Start 2-cycle hysteresis test and collect data simultaneously. The two-cycle hysteresis test has the following steps.
a) Elongate 200% at a constant rate of 20 "/ min.
b) Hold in that position for 30 seconds.
c) Go to 0% elongation at a constant rate of 20 "/ min.
d) Hold in that position for 60 seconds.
e) Elongate 50% at a constant rate of 20 "/ min.
f) Hold in that position for 30 seconds.
g) Go to 0% elongation.
(7) Calculate and report properties including stress relaxation at 200% elongation and strain%. Report the average results of 3 samples.
[0127]
C. Sustained load stress relaxation test
The properties measured by this method show how much the consumer feels from the product's side panels, waistband, or other elastic components after the product has been worn at body temperature for a specified period of time, and to what extent the product It can be correlated to fit. The properties measured by this method are related to the choice of material that resists relaxation under a sustained load at body temperature (about 100 ° F.) and that is continuously adapted over the maximum wearing time of the absorbent product.
[0128]
This test uses a tensile tester commercially available from Instron Engineering Corp., Canton, MA or SINTECH-MTS Systems Corporation, Eden Prairie, MN. The film is cut into test pieces 1 "wide x 2" long by MD. Mark the sample with a 1 "gauge length and wrap the sample with tape outside the gauge length symbol to give it a more grippable surface at the grip. Connect the instrument to a computer, test speed and others Control, test data, collect, calculate and report sustained stress relaxation at 100 ° F. (close to human body temperature) The procedure is as follows:
[0129]
(1) Select an appropriate grip and load cell for testing. The grip should be wide enough to mount the sample and typically uses a 1 "wide grip. The load cell has a tensile response coming from the test sample depending on the capacity or load range of the load cell used. A 50 lb load cell is typically used.
(2) Calibrate the instrument according to the manufacturer's instructions.
(3) Set the gauge length to 1 ″.
(4) Place the sample on the flat surface of the gripper according to the manufacturer's instructions.
(5) The crosshead speed is set to a constant speed of 10 "/ min.
(6) Start sustained load stress relaxation test and collect data simultaneously. The sustained load stress relaxation test has the following steps.
a) Elongate 200% at a constant rate of 10 "/ min.
b) Hold in that position for 30 seconds.
c) Go to 0% elongation at a constant rate of 10 "/ min.
d) Hold in that position for 60 seconds.
e) Elongate 50% at a constant rate of 10 "/ min.
f) Hold in that position for 10 hours.
g) Go to 0% elongation.
(7) Calculate and report characteristics including initial and final load (ie, final sustained load) and% loss. Report the average results of 3 samples.
% Loss is stress relaxation at 10 hours sustained load, [(initial load at 50% elongation of cycle 2-final load at 50% elongation of cycle 2 after 10 hours) / 50% elongation of cycle 2 Initial load at] x100.
[0130]
Examples
Various amounts of styrenic elastomeric copolymers such as Kraton G1600 series commercially available from Shell Chemical Company, Houston, TX, or SEPTON commercially available from Kuraray America, Inc., New York, NY Name) S4000 or S8000 series, vinyl arene resins such as polystyrene PS210 commercially available from Nova Chemical, Inc. Monaca, PA, and mineral oils such as Drakeol commercially available from Pennzoil Co., Penrenco Div., Karns City, PA. Name) to form an elastomeric mixture.
[0131]
Examples of suitable elastomeric compositions for use herein are shown in Table 1. The amount of each component is expressed as% by weight of the elastomeric composition. Additives, especially antioxidants, present in only small amounts are not shown in the compositions of Table 1. Typically, elastomeric compositions useful in the present invention comprise about 0.5% by weight antioxidant.
[0132]

The physical properties of the extruded monolayer film of the elastomeric composition of Table 1 are shown in Table 2. These physical properties are measured by the above test methods. All physical properties shown in Table 2 are represented by film samples of equal basis weight. Table 2 shows that replacing polystyrene with a low molecular weight aromatic hydrocarbon resin surprisingly reduces the total weight percent of the composition comprising the sterically intertwined network structure, but with comparable elasticity and stress relaxation. It shows that the characteristics can be obtained.
[0133]

The physical properties of Composition 1 shown in Table 3 are measured as an extruded single layer elastomeric film, as a coextruded multilayer film, and as a three-dimensional vacuum formed web.
[0134]
A flat coextruded multilayer film is produced and then formed into an elastomeric web as shown in the micrographs of FIGS. The coextruded film comprises three layers as shown in FIG. The central elastomeric layer comprises polystyrene and mineral oil, and optionally styrenic triblocks mixed with an aromatic hydrocarbon resin. The elastomeric layer is typically about 0.052 mm (3.2 mils) thick. The skin layers comprise a polyolefin material, each typically having a thickness of about 0.0038 mm (0.15 mil). The total dimensions of the film are about 0.09 mm (3.5 mils) and the elastomer layer is about 75-90% of the thickness. Single layer elastomeric films having a thickness of about 0.072 mm (2.8 mils) are also produced by methods generally known in the art. These films are cut to the appropriate sample size according to the test method described above.
[0135]
Although difficult to measure accurately, the dimension from the first surface to the second surface of the three-dimensional elastomeric web may be on the order of 1 mm for a suction ratio of about 10: 1. In the as-moulded, unstretched shape, the continuous first surface generally formed a regular pattern of 1 mm square liquid permeable openings spaced about 1 mm apart on all sides. . The secondary openings are slightly smaller than the primary openings and give the elastomeric web an open area of about 12-16%.
[0136]
Representative elastomeric webs of the present invention showed reliable elastic performance with no significant impact on web elasticity or porosity due to repeated, sustained web elongation up to about 400% or more. . In general, the web exhibited a higher modulus on the first stretch as the skin layer experienced inelastic strain. Thereafter, it was believed that microscopic wrinkles formed on the interconnect members in the area of inelastic skin layer strain, which resulted in a lower, generally constant web modulus.
[0137]

Sample 1a is an extruded single layer elastomeric film of composition 1 and sample 1b is a coextruded multilayer film having composition 1 as the central layer and polyethylene as the skin layer disposed on the opposing surfaces of the central layer. Yes, sample 1c is a three-dimensional elastomeric web formed from the multilayer coextruded film 1b by the method described above.
[0138]
All patents, patent applications (and any patents promulgated therewith, and correspondingly published foreign patent applications) and literature mentioned throughout this description are hereby incorporated by reference. However, none of the documents incorporated herein by reference is admitted to disclose or describe the present invention.
[0139]
While particular embodiments of the present invention have been illustrated and described, various other changes and modifications can be made without departing from the spirit and scope of the invention, as will be apparent to those skilled in the art. Accordingly, the claims are intended to cover all such variations and modifications as fall within the scope of the invention.
[Brief description of the drawings]
FIG. 1 is an enlarged, partial perspective view of a prior art polymeric web of the type generally disclosed in commonly assigned US Pat. No. 4,342,314.
FIG. 2 is an enlarged, partial perspective view of a preferred elastomeric web having a two layer polymer film of the present invention, at least one of which is elastomeric.
FIG. 3 is another enlarged partial view of a web of the type generally shown in FIG. 2, but illustrating in more detail the web structure of another elastomeric web of the present invention.
FIG. 4 is an enlarged cross-sectional view of a preferred multilayer film of an elastomeric web with an elastomer layer disposed between two skin layers of the present invention.
FIG. 5 is a plan view of the opening shape of another elastomeric web of the present invention projected onto the plane of the first surface.
6 is an enlarged cross-sectional view of the interconnect member as viewed along section line 6-6 in FIG.
7 is another enlarged cross-sectional view of the interconnect member as viewed along section line 7-7 in FIG.
8A schematically shows a cross-section of an opening of an elastomeric web of the present invention in various stretched states. FIG.
FIG. 8B schematically shows a cross-section of an opening of an elastomeric web of the present invention in various stretched states.
FIG. 8C schematically illustrates a cross-section of an opening in an elastomeric web of the present invention in various stretched states.
FIG. 9 is an enlarged optical micrograph showing a first surface of an elastomeric web of the present invention having a regular pattern of about 1 mm square openings.
10 is a perspective view of an enlarged scanning electron micrograph showing the second surface of the elastomeric web shown in FIG. 9 in an unstretched state.
FIG. 11 is a perspective view of an enlarged scanning electron micrograph showing the second surface of the elastomeric web shown in FIG. 9 in an approximately 100% stretched state.
FIG. 12 is a perspective view of an enlarged scanning electron micrograph showing wrinkles formed after stretching and recovery of the openings of the elastomeric web of the present invention.
FIG. 13 is a partially cutaway perspective view of a disposable garment comprising an elastomeric web of the present invention.
FIG. 14 is a simplified, partially cut away view of a preferred embodiment of a disposable garment side panel.
FIG. 15 is a simplified, partially exploded perspective view showing a laminate structure that is generally useful in forming the web structure shown in FIG. 2;
FIG. 16 is a perspective view of a tubular member formed by rolling a flat laminate structure of the type generally shown in FIG. 15 to a desired radius of curvature and joining the ends together.
FIG. 17 is a simplified schematic diagram illustrating a preferred method and apparatus for debossing and perforating an elastomeric film generally in accordance with the present invention.
FIG. 18 is an enlarged, partially cutaway perspective view showing another elastomeric web of the present invention.
FIG. 19 is an enlarged cross-sectional view of the web as seen along section line 19-19 in FIG.

Claims (12)

Stress having a thickness of 1.0 mil (0.0254 mm) to 5.0 mil (0.127 mm) suitable for forming into a porous, macroscopically expanded, three-dimensional elastomeric web A relaxed elastomeric film , wherein the elastomeric film is
a) 20-80% by weight of an elastomeric block copolymer, said copolymer comprising 10-80% by weight of at least one hard block and 20-90% by weight of at least two soft blocks. ),
b) 3 to 60% by weight of at least one vinylarene resin, and c) 5 to 60% by weight of process oil, the stress relaxation at 200% elongation at room temperature being less than 20%, 37.8 ℃ Ri stress relaxation less than 45% der after being stretched 10 hours 50% (100 ° F),
An elastomeric block copolymer comprising an ABA triblock copolymer, an ABBA tetrablock copolymer, an ABBABA block copolymer, and their Selected from the group consisting of mixtures, wherein A is a hard block derived from vinylarene monomers or a mixture of vinylarene and olefinic monomers, and B is a soft block derived from olefinic monomers Film . Vinylarene monomers, styrene, alpha-methyl styrene, is selected from the group consisting of contact and mixtures thereof, olefin monomer is selected ethylene, propylene, butylene, isoprene, butadiene, and mixtures thereof The film according to claim 1 . The number average molecular weight of the hard blocks is 1,000～200,00 0, the number average molecular weight of the soft block is 1,000～300,00 0, according to claim 1 or 2 films. Vinyl arene resin, styrene, alpha-methyl styrene, bi Nirutoruen, and it is derived from monomers selected from the group consisting of mixtures thereof, a number average molecular weight of vinyl arene resin is 600～200,00 0, the glass transition The film according to any one of claims 1 to 3 , wherein the temperature is 58 ° C to 180 ° C. The vinylarene resin is a mixture of polystyrene and low molecular weight aromatic hydrocarbon resin in a concentration ratio of polystyrene to low molecular weight aromatic hydrocarbon resin of 1:10 to 10: 1 , and the number average molecular weight of polystyrene is 10,000 to 100,00 0, the number average molecular weight of the aromatic hydrocarbon resins is 600～10,00 0 a film according to any one of claims 1-4. The block copolymer is styrene-butadiene-styrene (S-B-S), styrene-ethylene / butylene-styrene (S-EB-S), styrene-ethylene / propylene-styrene (S-EP-S), styrene. A styrene-olefin-styrene triblock copolymer selected from the group consisting of isoprene-styrene (S-I-S), hydrogenated polystyrene-isoprene / butadiene-styrene (S-IB-S) and mixtures thereof. The film according to any one of claims 1 to 5 , wherein the vinylarene resin is polystyrene and the process oil is mineral oil. A low stress relaxation elastomeric film suitable for forming into a porous, macroscopically expanded, three-dimensional elastomeric web, said elastomeric film having opposing first and second surfaces 7. An elastomer layer, and comprising at least one substantially less elastomeric skin layer substantially continuously bonded to the first surface of the elastomer layer, wherein the elastomer layer is any of claims 1-6 . A film comprising the composition according to claim 1. The film according to claim 7 , wherein the elastomer layer constitutes 20% to 95% of the total film thickness and the skin layer constitutes 1% to 40% of the total film thickness. The skin layer comprises a thermoplastic polymer selected from the group consisting of polyolefins, ethylene copolymers, polystyrene, poly (α-methylstyrene), styrenic random block copolymers, polyphenylene oxide, and mixtures thereof. The film according to claim 7 or 8 . Characterized in that it comprises the elasticity imparting portion comprising a low stress relaxation elastomeric film according to any one of claims 1 to 9 the product to be worn adjacent to the human body. 11. The product of claim 10 , wherein the product is a pant diaper, training pant, disposable diaper with a fixture, incontinence clothing, sanitary napkin, panty liner, dressing, bandage, or wrap . Before SL elasticity imparting portion waistband, side panels, cover (cuff), a absorbent product to be used as a topsheet or backsheet, product according to claim 1 0.

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